I have. I have an infrared sauna in my house. I use it about two times a week. I haven't had any cold since I've been using it. When I start to feel a cold coming on, I just go into the sauna and then it kills it off. I'm rather grateful I have one. My skin also looks amazing after I have one too. I can also think clearer, therefore I presume something positive is happening within my body. i.e. expelling toxins.

My sauna is just a little tyke - a tiny little baby of a sauna :p - http://www.divapor.com/sauna-solo-basswood/basswood-solo-sauna.php